I’m about 1/2 way through reading “How to be a stoic”, so far its a good introduction.

Stoicism is an ancient (yet timeless) philosophy from the Greek and Roman era. Basically, Stoics cultivate the basic virtues of Courage, Wisdom, Temperance and Justice, which lead to lasting happiness, success, love and all good things in life. “The man who has virtue is in need of nothing whatever for the purpose of living well.”

Famous stoics include the philosopher Seneca and Roman emperor Marcus Aurelius

Marcus Aurelius !

It's interesting that the main thinkers listed are all Roman. They're definitely the best known, but Stoicism was a Greek philosophy first and foremost, and Cleanthes, Chrysippus, etc. were more significant than any of the Romans.

Stoicism had a lot going for it, but it was also full of a lot of crazy nonsense - there's a reason you've never met a Stoic who was fully on board with Stoic natural philosophy or "physics." The logic eventually made a comeback (via Frege, possibly due to plagiarism!), and the virtue ethics got absorbed into Christian moral philosophy by about the 13th century (by way of neo-platonists who influenced Dominican philosopher theologians like Aquinas). It's not surprising that it ran out of steam.

Stoicism often gets conflated with apathy, which to some extent is a fair interpretation. But it’s not being indifferent to everything - rather, only to the things that disrupt your psychological stasis.

Then Silicon Valley ran with the idea and made it about tone-deafness. So now it’s almost fashionable to be intentionally cruel and tone-deaf, and then chalk it up to Stoicism.